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<p class="MsoNormal">Hey,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">So we’re working the revisions to the LTP spec, and one thing we’d like to do is to have a ‘field length identifer’ that serves (at least logically) as the index into a lookup table that gives the lengths of a number of LTP header fields.
So, for example field Length Identifier 1 could mean:<o:p></o:p></p>
<ul style="margin-top:0in" type="disc">
<li class="MsoListParagraph" style="margin-left:0in;mso-list:l0 level1 lfo1">The Session ID is 1 byte long<o:p></o:p></li><li class="MsoListParagraph" style="margin-left:0in;mso-list:l0 level1 lfo1">The Session Number is 3 bytes long<o:p></o:p></li><li class="MsoListParagraph" style="margin-left:0in;mso-list:l0 level1 lfo1">The Offset fields in data segments are 4 bytes long<o:p></o:p></li><li class="MsoListParagraph" style="margin-left:0in;mso-list:l0 level1 lfo1">Etc.<o:p></o:p></li></ul>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">We believe that the ‘lookup table’ should be a SANA registry (we’re currently envisioning maybe a couple of ‘profiles’ e.g. for low- medium- and high-rate links).<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I THINK we want to write the spec in such a way that we talk about the field length identifier and then say something like: “For field lengths determined by the field length identifier, implementations MUST use the field length values from
<insert SANA registry here>”.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Does this seem reasonable? Other thoughts / suggestions?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"> v/r,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"> --keith<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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